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1.
Testicular torsion is a dangerous urogenital disorder which is caused by twisting of spermatic cord, and unless immediate treatments happen at a proper time, oxidative stress, occurred during ischaemia reperfusion, finally leads to irreversible disintegration of testicular tissue. One of the first preventive lines is to administrate antioxidant factors. In the present study, we investigate the therapeutic effect of cerium oxide nanoparticle on the injury. We divided 45 rats into nine groups, subjected eight groups to testicular torsion–detorsion, injected different doses of cerium oxide nanoparticle into the peritoneum of six groups and analysed all the groups regarding spermatogenetic indices including sperm count, sperm viability and Johnson mean. Our results showed that cerium oxide nanoparticle can alleviate oxidative stress in testis, and this alleviation promotes the reproductive indices as the concentration of cerium oxide nanoparticles increases. The catalase-mimetic and superoxide dismutase-mimetic activities of cerium oxide nanoparticle are the most probable theories to explain the antioxidant effect of the nanoparticle.  相似文献   
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Methyl tertiary-butyl ether (MTBE) is used to reduce carbon monoxide and ozone in urban air and to boost fuel octane. There is a lack of knowledge in the literature about the histomorphometric changes of the testis following exposure to MTBE. Therefore, this experimental study was performed to determine the effect of oral exposure to MTBE on histologic and histomorphometric changes of testis in adult rat. A total of 25 adult male Sprague-Dawley rats were randomly divided into five equal experimental groups: control, almond oil and three treatment groups which received 400, 800 and 1600 mg/kg/day MTBE in almond oil by gavages for 30 consecutive days. Histomorphometric analysis showed no significant difference in absolute and relative testis weight, connective tissue thickness, germinal epithelium height, tunica albuginea thickness and Sertoli cell numbers between experimental groups (P>0.05). However, trend analysis showed that the seminiferous tubule diameter increased and interstitial cell numbers as well as spermatocyte and spermatid cell numbers decreased significantly in MTBE treated groups (P<0.05). It may be concluded that MTBE could exert adverse effects on spermatogenic cells in adult rat. Whether the observed changes in the present study are due to the direct effect of MTBE via passing blood-testis barrier or its indirect effect through another mechanism should be elucidated in future studies.Key Words: Histomorphometric, MTBE, Rat, Testis  相似文献   
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Background

Rehabilitation of injuries in the upper extremity and reestablishment of muscle strength throughout the range of motion in overhead movements, are the major concerns of athletes and coaches in the sports field.

Purpose

To determine the effect of eight-week “gyroscopic device” mediated resistance training exercise on grip strength, wrist and shoulder strength and proprioception, and upper extremity performance, in participants with impingement syndrome or tennis elbow.

Design and methods

For this study, in a university rehabilitation clinic 45 volleyball players (aged 22–28) purposefully were selected and divided into 3 groups: shoulder impingement (group I), tennis elbow (group II), and control (group III). The experimental groups performed the “gyroscopic device” mediated resistance training, three sessions a week over 8 wks. Grip strength, wrist and shoulder strength and proprioception, and upper extremity performance were measured before and after implementation of the intervention (eight-week resistance training using a “gyroscopic device”) using a hand hold dynamometer, isokinetic dynamometer, and Y balance test respectively.

Results

After 8 weeks of “gyroscopic device” exercise, improvement in the shoulder, wrist and grip strength, shoulder and wrist proprioception and performance scores of both experimental groups was significant. There were no significant differences between study groups I and II, both groups, however, demonstrated significant differences when compared to the control group, but between group I and the control group, and between group II and the control group, the difference was significant. However, no significant change was seen in the control group.

Conclusions

Due to the significant effects of the “gyroscopic device” mediated exercise on grip strength, wrist and shoulder strength and proprioception, and performance of the upper extremity, use of the exercise can be recommended for subjects with impingement syndrome or tennis elbow impairment in measured variables. More research is needed to confirm the result of this study.  相似文献   
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Micro-aeration as a pretreatment method improves the efficiency of anaerobic digestion of municipal sewage sludge and consequently promotes the methane production. In this study, adenosine triphosphate (ATP) and flow cytometry (FCM) were employed to monitor the performance of the micro-aerobic process and investigate the survival of bacterial cells within the process. At first, the effect of air flow rate (AFR) (0.1, 0.2, 0.3 and 0.5 vvm) on hydrolysis of mixed sludge in 5 aeration cycles (20, 30, 40, 48 and 60 hours) was examined. Then, the effects of the micro aerobic process on methane (CH4) production in anaerobic digestion were surveyed. The highest VSS reduction was 30.6% and 10.4% for 40 hours in the reactor and control, respectively. Soluble COD also fluctuated between 40.87 and 65.14% in micro-aerobic conditions; the highest SCOD was achieved at the time of 40 h. Microbial activities were increased by 597%, 170% and 79.4% for 20, 30 and 40 h pretreatment with the micro-aerobic process, respectively. Apoptosis assay showed that micro-aerobic pre-treatment at 20, 30 and 40 h increased the percentage of living cells by 57.4, 62.8 and 67.9%, respectively. On the other hand, FCM results showed that the highest percentage of viable bacteria (i.e., 67.9%) was observed at 40 h pretreating which was approximately 40% higher the ones for the control. Variation in cumulative methane production shows that methane production was increased by 221% compared to anaerobic digestion (control group). Therefore, ATP and FCM can be employed as two appropriate, accurate, relatively specific indicators for monitoring the process and bacteria viability.

Micro-aeration as a pretreatment method improves the efficiency of anaerobic digestion of municipal sewage sludge and consequently promotes the methane production.  相似文献   
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Background:

Approximately 5% of hepatitis B virus (HBV) carriers are coinfected with hepatitis D virus (HDV). HBV/HDV coinfection is a major cause of cirrhosis and end stage liver disease in chronic HBsAg carriers. The only approved therapy for chronic hepatitis delta is interferon alpha (IFN α) in either pegylated or conventional forms. Although higher doses and longer durations of IFN α therapy in HBV/HDV coinfected patients are currently applied, yet treatment response is low.

Objectives:

We aimed to determine the efficacy of IFN α-2b therapy in patients with HBV/HDV coinfection.

Patients and Methods:

In this cross sectional study, 20 HBsAg carriers with positive Anti-HDVAb and RT-PCR for HDV RNA were recruited and treated for three year duration with 5 million units (MU) of IFN α-2b, three times weekly or one year with 5 MU of IFN α-2b daily. Sustained virological response (SVR) was defined as a negative qualitative HDV RT-PCR, 6 months after treatment cessation.

Results:

Overall, 3 (15%) subjects achieved SVR, 10 cases (50%) relapsed after treatment cessation and 7 (35%) patients did not clear HDV during the treatment.

Conclusions:

HDV coinfection with HBV had very low response rate to high doses and long durations of IFN α-2b therapy.  相似文献   
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